The present specification relates generally to the field of medium or high voltage switches. More particularly, the present specification relates to bushings for medium or high voltage switches.
Switches (e.g., capacitor switches, vacuum interrupter based voltage switches, etc.) may be used to connect and disconnect electrical equipment from medium or high voltage lines. Switches typically include a vacuum interrupter inside of a bushing, and the operational and environmental requirements of medium or high voltage switches typically require the use of costly materials such as cycloaliphatic epoxy. An interrupter is typically installed in a bushing in one of two ways: (1) encapsulating the interrupter in a flexible material, such as urethane or silicone, and then encapsulating the flexible material into a cycloaliphatic epoxy, or (2) mechanically installing the interrupter in a cycloaliphatic epoxy bushing and using polyurethane to bond the interrupter to the bushing. These methods require costly materials and make it prohibitively difficult to salvage or repair an interrupter from a damaged bushing.
Therefore, there is a need for an improved medium or high voltage switch. There is also a need for a switch bushing that uses lower cost materials. There is further a need for a switch that permits repair and replacement of the interrupter in the bushing. Yet further, there is a need for a high or medium voltage switch that uses a low cost bushing material and meets environmental requirements of switching applications. There is also a need for a method of manufacturing a high or medium voltage switch using a low cost bushing material.